← Back to Quizzes Hints: 2/2 Number Set – 3 Easy Start Your name (optional): Share Certificate Browse Quizzes Play Again [{"type":"single","prompt":"72 \u00f7 3 \u00d7 (5 + 7) \u2212 4\u00b2 = ?","options":["256","268","272","276"],"answer":[2],"explanation":"72\u00f73=24; (5+7)=12; 24\u00d712=288; 4\u00b2=16; 288\u221216=272.","hint":"Do bracket \u2192 division \u2192 multiplication \u2192 subtraction."},{"type":"single","prompt":"35% of a number plus 45 equals 50% of the same number minus 15. What is the number?","options":["300","350","400","450"],"answer":[2],"explanation":"0.35x + 45 = 0.50x \u2212 15 \u2192 45+15 = 0.50x \u2212 0.35x \u2192 60 = 0.15x \u2192 x = 400.","hint":"Bring all x-terms to one side and constants to the other."},{"type":"single","prompt":"Find the next term in the series: 3, 10, 21, 36, 55, ?","options":["72","76","78","81"],"answer":[2],"explanation":"Differences are +7, +11, +15, +19 (each time +4). Next difference = 23 \u2192 55+23=78.","hint":"Look at the difference between consecutive terms."},{"type":"single","prompt":"What is the smallest 4-digit number divisible by 7, 9, and 11?","options":["1260","1323","1386","1452"],"answer":[2],"explanation":"LCM(7, 9, 11) = 693. Smallest 4-digit multiple of 693 is 693\u00d72=1386.","hint":"First find the LCM, then find its first 4-digit multiple."},{"type":"single","prompt":"The sum of the present ages of A and B is 56 years. Four years ago, A was twice as old as B. How old is A now?","options":["32 years","34 years","36 years","38 years"],"answer":[2],"explanation":"Let current ages be A and B.","hint":"Convert the words into two equations and solve simultaneously."},{"type":"single","prompt":"On \u20b910,000, the simple interest at 10% per annum for 2 years is compared with compound interest (compounded yearly) at the same rate and period. What is the difference (CI \u2212 SI)?","options":["\u20b980","\u20b990","\u20b9100","\u20b9110"],"answer":[2],"explanation":"SI = PRT = 10000\u00d70.10\u00d72 = \u20b92000.","hint":"Use SI = PRT and CI = P[(1+r)\u207f \u2212 1]."},{"type":"single","prompt":"How many 4-digit numbers greater than 3000 can be formed using digits 1, 2, 3, 4, 5 without repetition?","options":["48","60","72","96"],"answer":[2],"explanation":"Thousand\u2019s place can be 3, 4, or 5 \u2192 3 choices.","hint":"Fix the thousand\u2019s digit first, then permute the remaining digits."},{"type":"single","prompt":"In a class, the ratio of boys to girls is 5 : 7. When 8 boys join (and no girl joins\/leaves), the ratio becomes 7 : 9. How many boys were originally in the class?","options":["70","80","90","98"],"answer":[2],"explanation":"Let boys = 5k, girls = 7k.","hint":"Express both ratios using k, then form and solve a proportion."},{"type":"single","prompt":"A two-digit number has a digit sum of 11. When its digits are reversed, the new number is 27 more than the original. What is the original number?","options":["38","47","56","65"],"answer":[1],"explanation":"Let the number be 10a + b.","hint":"Use variables for digits (tens = a, units = b) and set up two equations."},{"type":"single","prompt":"A train goes from station A to B at 60 km\/h and returns from B to A at 40 km\/h. What is its average speed for the whole journey?","options":["45 km\/h","48 km\/h","50 km\/h","52 km\/h"],"answer":[1],"explanation":"Let one-way distance be d.","hint":"Use average speed = total distance \u00f7 total time (not average of speeds)."}]
